Finally found proof of sinewed crossbows

For a very long time I have been trying to find evidence that medieval makers sinewed wooden crossbow laths. As is so often the way I stumbled over it when I was looking for something else. I was looking for translations of Joseph Alm but found a translation of the rules for the crossbow makers of Venice by S.Manning on his website ‘Age of Datini’. There are a couple of rules that dictate the ways in which guild members may apply sinew to round wood bows, so yay, late 13th century Venetian crossbows were sinewed if the client requested it!


https://www.ageofdatini.info/fontes/rules-crossbow-makers-venice.html

Great find!!   Now we know for sure.  If the Venetians were doing it, chances are others were also.

There’s so much you might infer from the rules- guild members were allowed to routinely sinew the centre, presumably to prevent damage from the tiller and bindings but couldn’t sinew a lath in any other way until purchased- I guess to prevent defects being hidden under the sinew? Also, they could build wooden crossbows from two or three laths and reinforce the joints with sinew exactly like the Alhambra crossbow. And, as you say Venice was an international trade centre so if they knew about sinew, so did everyone. The fact that the quality and use of sinewing was put in guild rules implies a well established process, so that might mean it had been known for a long time. Are we looking at earlier than mid 1200s? Who knows but it is intriguing, isn’t it?

your reasoning makes sense.

But just for the record, Holger Richter (Die Hornbogenarmbrust , chapter 9.3 ) has a commentary on these rules based on translation by Alessio Cenni ( also referred here https://thearbalistguild.forumotion.com/t414-german-crossbow-1475 ).
And Richter&Cenni had the assumption that this text concerns only horn bows. Their interpretation of  "2 or 3 staves" either means full length strips of horn, and if assembled from smaller pieces the customer should be allowed to inspect the horn core before sinewing or that the bow must have more that a single strip of horn as minimum requirement.
 
 In any case the original text does not seem contain any explicit mention of wood or timber (at least in latin) . So there is room for interpretation.

So much is lost to history and working on assumptions is difficult at best. Some of the regulations deal with best practice in building horn bows but others seem to discuss round bows. I would expect wood bows to be round belly, horn to be flat. Personally, I am not convinced by interpreting “staves” as horn strips in the light of the Alhambra bow, but having attempted to build a horn core, having a couple of horn strips running right across the core would make life easier than building it entirely from small pieces. On the other hand, as a client, I might be unhappy at purchasing a core then waiting many months for the sinew to be applied, dried and cured, and there is no real guarantee that the core I inspected is the core covered in sinew and birch bark that was actually delivered. But then there are records in some guilds admonishing members following complaints of unscrupulous practices where high quality all-horn cores were ordered, and paid for, but inferior horn and brown oak cores were what was delivered…a pre-sinew inspection would sort of make sense… I can definitely see both sides in this


Thank you for the link, it’s not a thread I was aware of, I will go check it out straight away.

Here is a link to the original translation with notes on the Armour Archive forum.

http://forums.armourarchive.org/phpBB2/viewtopic.php?f=4&t=188319&p=2850232&hilit=Crossbow+Venice#p2850232

stuckinthemud1 wrote: Personally, I am not convinced by interpreting “staves” as horn strips in the light of the Alhambra bow,

  Exactly. It is also tempting to speculate that arcum rotundum would indeed be the guild term for "knottelarmbrust" aka. self bow. The round shape being the back with intact growth ring. There is no particular reason to make the belly of a wooden bow round, and there is no reason to make an unsinewed horn core round.
 
 A glossary of Venetian bow building terminology would of course be useful.
Speaking of which,
Richter refers to Johann Schmellings Bayreisches wörterbuch page 145 ( direct link : https://archive.org/details/bub_gb_apZBAAAAYAAJ/page/146/mode/2up   ) mentioning a German-Venetian dictionary from 1424.

 A German-Venetian vocabulary that can be found online :
 https://epub.uni-regensburg.de/16521/1/ubr06971_ocr.pdf
has several archery terms , but does not seem to have the specific entry that Schmelling was referring. (la stambechina - horn crossbow ) At least with that spelling.
 And of course these guild rules we are discussing here are written in Latin and not Venetian Italian .

I was a bit confused by the mention of soap but I guess it could be useful, if not even critical, to remove finger oils from horn surfaces before gluing with hide or fish glue. Or it has something to do with horn flattening process which usually involves boiling. 20 soldi is a pretty high penalty it would seem. Perhaps there are other interpretations? Fustis is associated both with soap and sinew, personally I'm not aware of uses of soap in making wooden bows.

Sinewing involves lots of soap.  The surface to be sinewed needs to be thoroughly degreased, and, yes, fingerprint oils are the main problem, but, some materials do contain oils that need to be scrubbed out.  Wood needs to be thoroughly degreased when you sinew it, as does horn. Sinew itself is very greasy, especially bovine sinew.  When I sinew I soak the sinew in soapy water, then clean water then the warm glue, even though I thoroughly cleaned/degreased the raw sinew before it was left to dry.  A requirement to use soap suggests some makers were inclined to wash the surface to be sinewed with water only.  Maybe soap was an expensive commodity in the 13th century?

I reread the part that mentions scanellum and I think you are right. It says an unsinewed bow can be sinewed after buying, which really doesn't make any sense in the case of horn composites or wood laminates because they are not even functional that way. Sinew can be optional only on a wooden prod made from a single piece of wood. There is a possibility those were unfinished blanks, but I can't see why someone would sinew a horn core blank in the scanellum and leave everything else bare. A prod with sinew backing added in the center only is not a blank, it's basically finished and ready for mounting. The point of this regulation would be to expose the natural condition of the back, otherwise all kinds of junk wood or bad workmanship might be hidden under the sinew.